Combined choke-coil and fuse.



J. L. FAY.

coMBlNED cHoKE COIL AND FUSE.

APPLICATION FILED OCT. I9. 1914.

Patented June 20, 1916.

ment a choke coil and a fuse,

aan orario JOHN L. FAY, OE' ST. LGUIS, MXSSC'UR.

COMBINE CWJKE--CL AND FUSE.

Specification of Letters Patent.

Application filed-October 19, 19M., Serial lilo. salgas.,

To all whom t may concern Be it known that I, JOHN L. l `Ar,'a citizenof the United States, residing at the city of St. Louis, State. ofMissouri` have invented a certain new and useful Improvement in CombinedChoke-Coilsl and Fuses, of which the following is a full, clear, andexact description, such as will enable others skilled in the art towhich it appertains .to make and use the same, reference being had tothe accompanying drawings, forming part of this specification, in which-Figure lis a vertical section taken through the center of a combinedchoke coil and fuse of my improved construction. Fig. 2 is a horizontalsection taken approximately/aon the line 2 2 of Fig. 1. Fig. 3 is a viewlooking against the bottom of the housing or shell of the device andshowing the removable member in horizontal section. F ig. 4 is anenlarged detail section taken approximately on the line 4 4: of Fig. 3.

My invention relates to a combination fuse and choke coil, the principalobject of my invention being -to combine in one-ele and which device isparticularly intended for the protection of transformers intransmissionlines or distribution circuits.

It will be understood that when, during a storm accompanied bylightning, the induced discharge encounters an inertia or inductance, avery great electro-motive force is created between the terminals of theparticular portion of the circuit which vis immediately adjacent to ythelightning discharge. Thus, a suddenrush of current coming in over atransmission line or distribution circuit encounters the highlyinductive windings of wire in the transformer locatedy in said circuit.

The inductance of the windings yin the transformers dams or chokes therush of current, which action very frequently causes a break-down oftheprimary and secondary windings or effects aground tothe transformercase, and which result is caused by the'built-up rise in voltageproduced by high frequencies resulting from a lightning stroke or byinduced charge of high frequency from an 'adjacent lightning stroke., Asa result, the transformer is destroyed and the secondary circuit towhich the consum- -ers are connected is rendered unserviceable,

and this necessitates expensive repairs besides loss of service ,oconsumers.

rasanten aune ao, reis, y

lt is the present practice to utilize in the connection from thetransformer to the primarysystem of wires a device known .as a

primary fuse block or fuse cut-out, which l' when the coils of atransformer are punc? tured by a lightning discharge, it permits of arush of current to flow, due to short circuited coils. This excessiverush of current causes the fuse to nelt in the primary cutout, and suchaction very frequently results in the destruction of said primarycut-out by reason of the high temperatures produced from the sustainedarc through the .gaseous vapors.

lt is thepurpose of my )invention to overcome the undesirable resultsjust referred to, and to provide a comparatively simple, inexpensive'and easily applied device which combines a choke coilwith ya fuse,which not only protects a transformer as a fuse' device, but dams orchokes the rush of current prou duced from lightning, thereby producing'a rise in potential on the lightning arrester side of the line thatcompels the lightning arrester to act in the manner intended.

'With the -foregoing' and `other.objects in view, my 'invention consistsin certain novel features of construction and arrangement of parts,hereinafter more fully described and claimed.

Referring by numerals to the accompany- 'mg drawings, l0 designates thehousing or shell which receives the plug Vor member which ycarries thechoke coil and fuse, said housing being preferably constructedv of glassor porcelain and of hollow` cylindrical shape and having its upperendclosed. The lower open end of this shell or housing is provided with anintegral depending flange or apron 11. Formed through thisl apron and onopposite sides thereof are inclined apertures 12 `through which pass theterminals of a' line or circuit, and the ends of these terminals areconnected in any suitable manner "to pairs of contactplates 13, the samebeing xed to the shellor housing on the shoulder between the bodythereof and the apron 11.

' The removable member which carries the choke coil and fuse is formedof suitable main body portion ll and a handle portion 15. Both body andhandle portions are cylindrical in form and formed integral therewith ata point between thevbody and handle is an outwardly projecting' flange16 which serves to protect the hand of the operator while the detachablemember is being placed in. or removedv from position within the housingor shell. A correspond ing protecting flange 1'? is formed integral withthe lower end of the handle portion 15. Formed through the body and,handle portions is an axially disposed bore or passage way 18 andlocated in the upper lportion of this bore or passage way is a tubularlining 19 of fire-proof insulating material such as asbestos, transiteor analogous material'. Formed in the surface of the body 14 is aspirally disposed groove 20 in whlch is located a section of wire 21which serves as the choke coil of the device. The lower end of thissection or coil of wire is connected to a bracket 22 which is liked toand projects outwardly from the lower portion of the body 1l, and saidbracket is adapted to engage between a pair of the contact plates 13.The upper end of the body 14 is tapered or made conical as shown in Fig.1, and the upper end of the coil 21 is connected to a contact plate 23,which latter is fixed to the tapered upper end of said body.

A fuse wire 24 extends through the upper portion of the tubular liningr19 and the upper end of said fuse is fixed in any suitable manner` tothe contact plate 23. The lower portion of said fuse is threaded throughaninclined bore or passage way 25 which is formed in the lower portionof the body 14 and the lining 19. The lower end of this bore or passageway terminates adjacent to the flange 16 and the end of the fuse whichprojects from said lower end is attached in any suitable manner to an.outn Wardly projecting bracket 26, the same be ing oppositely disposedwith respect to the bracket 22, and said bracket 26 is adapted to engagebetween a pair of the Contact plates 13. Positioned on the conical ortapered upper end of the body le is a conical cap 27 the same serving toclose the upper end of the bore or passage way 'through the body 14 andalso to cover the contact plate 23. Fixed in any suitablemanner to theside of the housing 10 is an outwardly projecting-bracket 28, and fixedthereto is an inverted L-shaped member 29, the horizontal leg. of whichis slotted as vdesignated by 30. The horizontal leg of a second invertedL-shaped member 31 overlies the horizontal leg of said member 29 andpassing through a slot 32 formed in the horizontal leg of said member 31and 'through the slot 30A is a Ibolt 33, the lower end of whichlreceives: av nut 34. The members 29 and 31 are adapted to engage across arm, thereby sup 'ing the fuse and choke coil memoir porting thehousing and the member carryin proper position. By making the member 31adiustable with respect to the member 29 the support can be appliedtocross arms of various widths.

When the removable member' carrying the choke coil and fuse is to bepositioned in the housing, the operator grasps the handle portion 15.015said removable member and the wide flanges 16 and 17 serve to protectthe hand against contact with the plates 13 or from an accidentalblow-out of the fuse resulting from short circuit while the device isbeing assembled. The body portion 14 is now moved upwardly into thehousing 10 until the brackets 22 and 26 strike against the shoulderbetween the body of the housing and the apron 11. The operator nowpartially rotates the removablel member so as to position the brackets22 and 26 between the pairs of contact plates 13 and thus the fuseandchoke coil are brought into circuit with the terminals of the linewhich are connected to the pairs of plates 13. In ycase the :fuse blowsout the melted metal and-gases resulting from such. blowout willdischarge downwardly through the opening in the tubular lining 19, andthrough the opening 18 inasmuch as this discharge is prevented fromfinding exit through the upper end of the detachable member by' the cap2'?A which, as heretofore stated, closes the opening at the upper end ofsaid removable member.

It will be understood that the size of the choke coil and the size ofthe wire of which said coil is formed may vary to meet the requirementsof various voltages and frequencies. For illustration, a choke coilthree inches long, one inch in diameter and comprisingr ten turns of #10copper wire will produce a potential of .00063 volts at a normal fullload current of 20 amperes at cycles.` The frequency of the avera elightning discharge may safely be said to e of many thousands cycles andas the potential across a reactance varies directly with the frequencyit will be understood that under such conditions a potential of severalhundred volts will be produced across the terminals of a coil ofapproximately the dimensions just mentioned and as a result theinductive windings of the transformer adjacent to the coil will beprotected inasmuch as the built-up lightning discharge is forced to ilowacross the air' or spark gap of the adjacent lightning arrester. Thecoil also has the effect of damming or choking the rush of current,thereby preventing strain on the transformer i windings, reducingbreak-down of transformer insulation and the interruption of service tothe consumers. The use of such a coil; so preventsvdamage to primaryfuse blocks inasmuch as the arc lli Lievens is reduced and likewise theeffects of a sus-v the lower end of said housing, ,andthus thechokecoilpfuse and contact plates are effectively protected againstrain, snow and ice and whenv itbecomes necessary to replace a blown outfuse the removable member can be readily detached and a new fuse placedin position .by removing the cap l? and threading the fuse wire throughthe inclined passage way and the passage way through the center of thelining 19.

device of my improved construction is comparatively simple, cheaplymanufactured, and -forms an eilicient protection lor transformers andlike devices against 'abnormal and destructive 'eurrentskcoming in overatransmission line or distributionycircuit.

y lt will berea'dilyunderstood that minor changes, `in the size, lformand construction of the variousparts of my'improved choke` coil andtusecanbe made and substituted for those herein shown and described, withoutdeparting' from the spirit of my invention, the scope ory which is setforth in the appended claims.

l claim:

1. In a device of the classdescribed, the combination with ahousingfprovided with contacts vwith which'the terminals of a circuitare connected, of a tubular member removably positioned within saidhousing, the upper end of said member being closed and vits lower endopen, attaching members on said removable member for engaging thecontacts on the housing, a choke coil on the removable member, whichchoke coil is connected to one of the attaching members, a fuseconnected to said choke coil and passing partially through the tubularmember, which fuse is connected to ,2. In a device of the classdescribed, the

combination.k with ahousing havin con-y tacts, of "atubular memberremovab ypositioned. .said housing," attaching devices on said tubularvvmember whichl vare adaptedy can be easily. 'and the other of thevattaching devices of said removable mem'-` ber, a tubularfhandledepending from the tubular member, a flange between said tubu lar member'and tubular handle, and a flange' at'the lower end of saidtubularhandle.

choke coil is connected to one of the attaching devices, a fuseextending through said tubular member andv connected ynear the upper endthereof to the choke coil, the lower end of said fuse being connected tothe other one oi' the attaching devices, a comparatively widehor'zontally disposed flange at the lower end of the tubular member, atubular hand-le depending from the tubular member, a. comparatively wideflange at the lower end of said tubular handle, and' a cap removablypositioned on the upper end of the tubular member and closing theopening therethrough. i

- 3. ln a device of the class described, the

combination with ahousing provided withy contacts with which theterminals of .a cir-y cuit are connected, oi a tubular member removablypositioned within said housing, attaching devices on said removablemember for engaging the contacts on the housing, a choke coil wound uponsaid tubular member, one end of which choke coil isv connected to' oneof the attaching devices, a fuse extending partially through theltubular member, and connected near the upper end thereof to the chokecoil, the lower end of said fuse being connected to the other one of theattaching devices, and a cap removably positioned on the` upper end ofthe tubular member and normally closing the opening therethrough.

e. ln a device o'l2 theclass described, the

combination with a housing provided withA contacts with whichv theterminals of a circuit are connected, of a tubular member removablypositioned within said housing, attaching devices on said removablemember Jfor engaging the contacts on the housing, a choke, coil woundupon the outer face of said .tu'blilar member, one end or whichchokecoil isr connected to one of the attaching devices, a fuseextending partially through the tubular memberand connected near theupperv end' thereof yto the choke coil, the lower end of said v'fusebeing connected to the other one oftheattaching devices, a capremovablyl positionedon'fthe tubular member. p

` 5.. Ina device of the 'class described, the

combination with a housing having contacts to j which the terminals of aline are connected, of a tubular member removably positioned in saidhousing, attaching devices on said member which. are adapted to engagethe contacts onthe housing, a choke g coil' Wound upon :theouter face ofsaid tubular member, one end of which choke coil is connected to oneofthe attaching devices, a fuse extending-partially through the tubularmember, there Abeing an inclined aperture formed through the Wall of thetubular member "ehroogh which the lower portion of the fuse posees, uheower end of seid fuse being' Connected @to the other one of eheotauehing devices, and the upper end of seid fuse being' connected atthe hop of the rubw ler member to the choke eoil.,

6. In a device of the eines described, bhe Combination with a housinghaving" comercio 'to which the eei'niinals of a line are connec1ted, ofo tubular member removably posi-- eioned in seid housing, attachingdevices on said member which aire adopted to engage the contacts on ehehousing', o choke eoii wound upon 4the outer :fece oiI seid tubularmember7 one end oi `which choke ooi?, is coni neeted to one oi theeimehing devices, fuse extending' partially through the tubo lar member,there being on inchned oper Lioneoe eure formed through the wall of thetubular member through which the ower portion. of the fuse passes, theower end of said fuso being connected to the other one of the nt-'mehing devices and the upper end of said fuse being connected :1t thetop of the tubuhir member to the choke coil, and a cup removablypositioned on the upper end of the itubnior member for closing theopening therethrough.

in testimony whereof I hereunto ax my alture in the presence of twoWitnesses,

17th dey of etober, 1914.

JOHN L. FAY.

nWitnesses P. SMITH, M. A. HANDEL.

